how can i remove the fuel oil oder from cement floor and terra cotta tile floor?

Simple Green should do the job. Pour it on,let it work for a while,mop up and rinse with water.

My first thought was to use kitty litter and grind it into the floor in the area to help absorb and help with the smell. I also thought about Dawn dish soap, because that stuff fixes everything! However, since I have no experience with this myself, I ventured out a bit and tried to find out what others' had to say, and this is what I discovered:

Kitty litter clumps and makes a mess, however a product called Diamataceous Earth works much better. If you would like more information, I have sited the web site below. Good luck to you!

there are products that have enzymes that actually eat breakdown petroleum products, I've bought them at cosco in the past but honestly I cant recall the name. worse case scenario try a power washer with hot water and a bleach solution, you might have to go back over it a few times but it will get better every time. you might try simple green on a small area with hot water and a scrub brush and see how it works. I use it to degrease my engine compartment so it should work for you. open windows in the mean time and have a couple fans going that should help as well